Monolithic Power Systems Inc. MP2224GJ-Z

Overview

MP2224GJ-Z from Monolithic Power Systems is a synchronous step-down DC-DC converter IC with integrated 70mΩ/25mΩ MOSFETs, delivering up to 4A output current across a 4.5V–18V input range and adjustable down to 0.6V output voltage. It operates at a fixed 500kHz switching frequency with current-mode control, enabling fast transient response in notebook I/O power and flat-panel TV applications.

For engineers reviewing the MP2224GJ-Z datasheet, MP2224GJ-Z pinout, MP2224GJ-Z application, or MP2224GJ-Z equivalent, key selection criteria include its TSOT23-8 package footprint, internal soft-start (2.4ms), ±1% reference accuracy, hiccup-mode over-current protection, and external clock synchronization capability (200kHz–2MHz).

Technical Context

The MP2224GJ-Z uses peak-current-mode control with an internal 500kHz oscillator and supports external clock synchronization via the EN/SYNC pin. Its error amplifier compares FB voltage against a 600mV internal reference and drives COMP to regulate inductor current through the high-side switch.

It integrates advanced asynchronous modulation (AAM) for light-load PFM operation, reducing quiescent current to 320μA typical. The bootstrap circuit powers the high-side gate driver using an external BST capacitor, with internal UVLO (2.6V) and regulation clamping to 5V.

Key Specifications

Pinout & Package

MP2224GJ-Z is housed in an 8-pin TSOT23 package (3.0mm × 3.0mm × 0.9mm), optimized for high-density PCB layouts and thermal performance with exposed pad grounding (GND pin 4). The package supports reflow soldering per JEDEC J-STD-020 and features RoHS-compliant, halogen-free construction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous step-down converter applications.

Compared with MP2224GJ-Z, MP2234GJ-Z offers higher current headroom and slightly better efficiency at full load, while TPS54340DDAR trades integration for wider input range and higher-frequency operation-neither is pin-compatible, and both require layout and compensation redesign.

Availability

MP2224GJ-Z is available at Aetrix Electronics and suitable for flat-panel television power supplies, notebook I/O subsystems, and digital set-top box SoC core rails requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for MP2224GJ-Z includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and power ICs, with design centers in the US, China, and Taiwan, and global distribution since 1997.

The MP22xx series targets space-constrained, high-efficiency DC-DC conversion in consumer and computing applications, emphasizing integration, thermal robustness, and ease of use with minimal external components.

FAQ

What is the minimum recommended output capacitance for stable operation?

The MP2224GJ-Z is optimized for ceramic output capacitors ≥22μF total (e.g., two 22μF X5R 10V devices). Lower values risk instability or excessive ripple; the internal compensation assumes ≥15μF effective capacitance with ESR <10mΩ. For 3.3V/4A designs, 44μF total is recommended to meet transient response and ripple targets.

Can MP2224GJ-Z operate with input voltage below 4.5V?

No-its absolute minimum operating input is 4.5V per datasheet specifications. Below this, UVLO prevents startup, and internal VCC regulation fails. Attempting operation at 4.2V or lower may cause erratic behavior or failure to regulate. For sub-4.5V inputs, consider MPS's MP2143 (2.5–6V input) or similar low-VIN buck converters.

Is an external bootstrap diode required for reliable operation?

An external bootstrap diode (e.g., 1N4148) is recommended only when VIN < 5V AND duty cycle >65%, or when VIN – VOUT < 2.6V. Under standard 12V→3.3V operation, the internal bootstrap circuit suffices. Adding the diode improves light-load efficiency and eliminates BST-related ripple but increases BOM count and layout area.

How does the hiccup-mode over-current protection behave during a sustained short circuit?

When FB voltage drops below 300mV for >100ms, the MP2224GJ-Z enters hiccup mode: it disables switching for ~10ms, then attempts restart. This limits average short-circuit current to ~1.2A and junction temperature rise, preventing thermal runaway. Recovery is automatic once the fault clears and FB rises above 400mV.

What is the maximum allowable PCB trace length between BST and SW pins?

The BST-to-SW trace must be ≤2mm in length and ≥0.3mm wide, with no vias or splits. Longer traces increase parasitic inductance, causing BST voltage droop and high-side gate drive failure-especially during PFM light-load operation. Place the 0.1μF BST capacitor directly across BST and SW pads with shortest possible connections.

Does MP2224GJ-Z support power sequencing with other rails?

Yes-via the EN/SYNC pin. Driving EN high after upstream rails stabilize ensures controlled startup order. For reverse sequencing (e.g., VCC before IN), use a simple RC delay on EN. The 1.4V enable threshold and 160mV hysteresis provide noise immunity; no external sequencer IC is needed for basic two-rail coordination.

What is the thermal resistance (θ_JA) of MP2224GJ-Z in standard layout?

Measured per JESD51-7 on a 4-layer PCB with 2oz copper, θ_JA is 100°C/W. With proper thermal pad connection to inner GND planes and ≥4 thermal vias, actual board-level θ_JA can reach 65–75°C/W. At 4A/12V→3.3V, power dissipation is ~1.2W; thus, ΔT ≈ 85°C above ambient with standard layout.